This research project continues to elucidate the reaction mechanisms involved in the metabolism of L-lysine to delta1-piperideine-2-carboxylic acid (P2C), P2C to L-pipecolic acid, L-pipecolic acid to delta1- piperideine-6-carboxylic acid (P6C), P6C to L-alpha-amonoadipic acid (AAA), and AAA to alpha-ketoadipic acid. It will isolate, purify to homogeneity and characterize L-lysine oxidase, P2C reductase, pipecolate oxidase, L-alpha-aminoadipic delta-semialdehyde (or P6C) oxidoreductase, and alpha-aminoadipate:alpha-ketoglutarate aminotransferase in the brain. It will isolate, purify and compare the characteristics of pipecolate oxidase localized in the peroxisomes and mitochondria. Mono- and polyclonal antibodies against L-lysine oxidase, P2C reductase, pipecolate oxidase, P6C oxidoreductase and alpha-aminoadipate:alpha-kekoglutarate aminotransferase in the rat brain will be prepared. The regional distributions of L-lysine oxidase, P2C reductase, pipecolate oxidase, P6C oxidoreductase and alpha-aminoadipate:alpha-kekoglutarate aminotransferase in the rat brain through enzyme activity study and immunocytochemical study. It will examine the developmental aspects of enzymes in the L-lysine pathway through enzyme activity assays and immunocytochemical study. It will examine the effect of L-alpha- aminoadipic acid and other lysine metabolites on the purified kynurenine aminotransferase and in astrocyte cultures. It will study the uptake of L-AAA in the astrocytes through cell cultures.